Article
Environmental Sciences
T. Gaubert-Bastide, S. Garambois, C. Bordes, C. Voisin, L. Oxarango, D. Brito, P. Roux
Summary: The study focuses on monitoring groundwater level changes using high-resolution geophysical methods and recovering seismic wave velocity changes through passive seismic interferometry. The experiment shows that seismic velocity variations are directly related to changes in water level and water saturation within the unsaturated zone, aiding in the understanding and modeling of water flow dynamics.
WATER RESOURCES RESEARCH
(2022)
Article
Environmental Sciences
Yang Song, Rui Hu, Quan Liu, Huiyang Qiu, Xiaolan Hou, Junjie Qi, Bernard Konadu-Amoah
Summary: This study aimed to evaluate the utility of multiple inversion techniques on aquifer heterogeneity characterization. A series of warm water injection tests were simulated in a fluvial aquifer analogue outcrop, and the calculated head and temperature datasets were used with the four above-mentioned inversion methods to reveal the aquifer heterogeneity. The results showed that thermal tracer tomography, hydraulic travel time, and attenuation tomography accurately characterized the high permeability zones within the well area, while the geological statistical method depicted the overall distribution of K values for a larger area. By comparing and combining the individual inversion results, the scientific and economic complementarity can be studied, and valuable advice for the choice of different inversion methods can be recommended for future practices.
Article
Water Resources
Lukas Roemhild, Gianluca Fiandaca, Linwei Hu, Laura Meyer, Peter Bayer
Summary: This study presents a new inversion procedure that allows for the direct computation of hydraulic conductivity (K) in an aquifer using induced polarization (IP) data. The novel approach was successfully implemented and showed a similar quality compared to hydraulic tomography. The results highlight the accuracy of the inversion and the significance of the proposed calibration strategies.
ADVANCES IN WATER RESOURCES
(2022)
Article
Environmental Sciences
Lisa Maria Ringel, Mohammadreza Jalali, Peter Bayer
Summary: This study presents an approach for stochastic characterization of geometric and hydraulic parameters of a 3D discrete fracture network (DFN) based on hydraulic tomography data and estimation of their uncertainty through Bayesian framework and Markov chain Monte Carlo (MCMC) methods. The method is effective in identifying variable fracture locations and orientations, especially for preferential flow paths, and discriminating fractures based on reliability. Additionally, it demonstrates the calibration of hydraulic apertures with fracture geometries and the necessity of complementing hydraulic measurements with additional information for successful inversion.
WATER RESOURCES RESEARCH
(2021)
Article
Engineering, Civil
Quan Liu, Rui Hu, Linwei Hu, Yixuan Xing, Pengxiang Qiu, Huichen Yang, Steffen Fischer, Thomas Ptak
Summary: The study modified the inversion framework of thermal tracer tomography to improve the characterization of hydraulic properties in fractured aquifers. Results show that the modified method can efficiently identify fractures connectivity and conduct hydraulic property characterization accurately under different conditions.
JOURNAL OF HYDROLOGY
(2022)
Article
Engineering, Civil
Yi Yu, Lutz Weihermueller, Anja Klotzsche, Lena Laerm, Harry Vereecken, Johan Alexander Huisman
Summary: This study compared the performance of sequential and coupled inversion workflows in obtaining soil hydraulic properties from horizontal borehole GPR data. The results showed that sequential inversion did not provide accurate estimates, while the coupled inversion approach provided accurate estimates of hydraulic properties in both synthetic modelling studies and actual field data. The study concluded that coupled inversion should be preferred over sequential inversion for horizontal borehole GPR data when strong SWC gradients occur during infiltration events.
JOURNAL OF HYDROLOGY
(2021)
Article
Geosciences, Multidisciplinary
Yu-Li Wang, Tian-Chyi Jim Yeh, Fei Liu, Jet-Chau Wen, Wenke Wang, Yonghong Hao
Summary: This paper utilizes triggered lightning as a point source for electromagnetic tomographic survey to image 3-D subsurface electrical properties in basins. It introduces a new temporal moment approach that overcomes the challenges in modeling 3-D Maxwell's equations with heterogeneous parameter fields. The results show that this approach can detect signals within a radius of 20-70 km and is suitable for mapping subsurface electric conductivity heterogeneity.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Environmental Sciences
Alex Sendros, Mahjoub Himi, Esmeralda Estevez, Raul Lovera, M. Pino Palacios-Diaz, Josefina C. Tapias, M. Carmen Cabrera, Francisco J. Perez-Torrado, Albert Casas
Summary: Traditional soil sampling techniques may not effectively evaluate the geometry and hydraulic properties of the unsaturated zone, while electrical resistivity tomography can provide more accurate geological information. This method can be applied in volcanic areas to quantify hydrological characteristics through electrical resistivity parameters measurement.
Article
Engineering, Civil
Huiyang Qiu, Rui Hu, Ning Luo, Walter A. Illman, Xiaolan Hou
Summary: This paper compares the performances of travel-time based inversion (TTI) and geostatistical inversion (GI) approaches in hydraulic tomography (HT). The results show that TTI can better reveal the structural features of high-diffusivity zones and requires less data for inverse modeling. On the other hand, GI can estimate parameters throughout the simulation domain, better characterize low-diffusivity zones, and generate the best estimated tomogram for accurate drawdown predictions.
JOURNAL OF HYDROLOGY
(2023)
Article
Engineering, Civil
Zhanfeng Zhao, Walter A. Illman
Summary: Hydraulic tomography has been developed as a robust technique for characterizing subsurface heterogeneity, but geostatistically-based inversion approaches may lack geological features when observation data is sparse. In this study, local hydrostratigraphic layers of glaciofluvial deposits were derived from corrected pressure logs collected during HPT surveys, and site-specific geological models were developed and calibrated to predict drawdown data of multiple pumping tests. The calibrated geological models outperformed geostatistical inversion approaches in predicting independent pumping tests, demonstrating the usefulness of integrating stratigraphic information derived from HPT logs for capturing sharp boundaries in hydraulic conductivity fields.
JOURNAL OF HYDROLOGY
(2022)
Article
Computer Science, Interdisciplinary Applications
Andres Gonzalez-Quiros, Jean-Christophe Comte
Summary: Groundwater model calibration is often hindered by limited hydrogeological data availability, but non-intrusive geophysical methods can provide higher spatio-temporal resolution datasets to identify hydrological processes and estimate hydraulic properties. Coupled inversion methods supplement hydrogeological datasets with auxiliary geophysical data, offering multiple calibration and uncertainty analysis options for a broad range of environmental models.
ENVIRONMENTAL MODELLING & SOFTWARE
(2021)
Article
Engineering, Civil
Yi Yu, Johan Alexander Huisman, Anja Klotzsche, Harry Vereecken, Lutz Weihermueller
Summary: This study proposes a workflow for coupled GPR full-waveform inversion (CFWI) to estimate soil hydraulic properties. The research finds that CFWI can accurately estimate the thickness of soil layers and provide precise water retention and hydraulic conductivity functions.
JOURNAL OF HYDROLOGY
(2022)
Article
Water Resources
Yaqiang Wei, Jian Chen, Lu Li, Ganghui Zhu, Yi Wen
Summary: This study aims to find reasonable data selection strategies to accurately estimate the hydraulic properties in DFN models. It demonstrates the feasibility of using HT to identify hydraulic properties in DFN models with high heterogeneity, and shows that inverse models can estimate hydraulic conductivity using steady-state conditions due to minimal storage effects. This research contributes to the use of HT surveys for mapping fracture zones.
HYDROLOGICAL SCIENCES JOURNAL-JOURNAL DES SCIENCES HYDROLOGIQUES
(2021)
Article
Optics
Rui Cao, Jingjing Zhao, Lei Li, Lin Du, Yide Zhang, Yilin Luo, Laiming Jiang, Samuel Davis, Qifa Zhou, Adam de la Zerda, Lihong Wang
Summary: Optical-resolution photoacoustic microscopy can visualize wavelength-dependent optical absorption at the cellular level. However, it has a limited depth of field. To overcome this limitation, needle-shaped beam photoacoustic microscopy is proposed. This approach extends the depth of field and provides new perspectives for slide-free intraoperative pathological imaging and in vivo organ-level imaging.
Article
Geochemistry & Geophysics
Fan Li, Kai Lu, Zhenyu Li
Summary: This study presents an application framework for directional gradient constraint on 2D unstructured triangular meshes. By properly meshing the underground space and imposing appropriate constraints, the accuracy of groundwater location and water content determination can be effectively improved. Field studies demonstrate that this method significantly enhances the identification of water table, soil interfaces, and abnormal groundwater locations.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Water Resources
Hojat Ghorbanidehno, Jonghyun Lee, Matthew Farthing, Tyler Hesser, Eric F. Darve, Peter K. Kitanidis
Summary: Riverine bathymetry is important for shipping and flood management, and indirect measurements with sensor technology can be used to estimate river bed topography. Physics-based techniques are computationally expensive, while deep learning offers a data-driven approach with potential for efficient training using limited data. The proposed method combines DNN with PCA to image river bed topography using flow velocity observations, showing satisfactory performance in bathymetry estimation with low computational cost and small number of training samples.
ADVANCES IN WATER RESOURCES
(2021)
Article
Geography, Physical
C. J. Roland, L. K. Zoet, J. E. Rawling, M. Cardiff
Summary: The study indicates that freeze-thaw environmental factors have a significant impact on the erosion of coastal bluffs at seasonal timescales, leading to increased pore pressures and frequent mass wasting events. Seasonal upslope erosion is primarily influenced by rising water levels and freeze-thaw processes, necessitating the inclusion of these transient conditions in landscape change models.
Article
Engineering, Environmental
Mojtaba Forghani, Yizhou Qian, Jonghyun Lee, Matthew W. Farthing, Tyler Hesser, Peter K. Kitanidis, Eric F. Darve
Summary: This study proposes a two-stage process utilizing principal component geostatistical approach to estimate bathymetry probability density function and multiple machine learning algorithms to solve shallow water equations (SWEs) efficiently. The first stage predicts flow velocities without direct bathymetry measurement, while the second stage incorporates additional bathymetry information for improved accuracy and generalization. Fast solvers are capable of accurately predicting flow velocities with variable bathymetry and BCs at a significantly lower computational cost compared to traditional methods.
STOCHASTIC ENVIRONMENTAL RESEARCH AND RISK ASSESSMENT
(2021)
Article
Environmental Sciences
Xueyuan Kang, Amalia Kokkinaki, Peter K. Kitanidis, Xiaoqing Shi, Jonghyun Lee, Shaoxing Mo, Jichun Wu
Summary: Characterizing the architecture of dense nonaqueous phase liquid (DNAPL) source zones is crucial for designing efficient remediation strategies, but traditional drilling investigations provide limited information and affect the accuracy of geostatistical methods. By parameterizing the DNAPL saturation field using a physics-based approach, improved prior descriptions and better resolution can be achieved in characterizing the source zones. Additionally, incorporating hydrogeological and geophysical datasets in the inversion framework can further enhance the performance of the method.
WATER RESOURCES RESEARCH
(2021)
Article
Geosciences, Multidisciplinary
Jeremy R. Patterson, Michael Cardiff
Summary: Characterizing aquifer properties and their associated uncertainty is a challenge in hydrogeology. Using oscillatory flow interference testing can help characterize aquifer flow properties. Studies show that multi-frequency testing improves inversion performance and decreases parameter uncertainty.
Article
Mathematics, Interdisciplinary Applications
Peter K. Kitanidis
Summary: This paper discusses the application of covariance and Fisher information matrix in inverse problems, as well as a reexamination within the Bayesian framework, proposing a lower bound for the covariance of the posterior probability density function.
GEM-INTERNATIONAL JOURNAL ON GEOMATHEMATICS
(2021)
Article
Geosciences, Multidisciplinary
Catherine Christenson, David J. Hart, Michael Cardiff, Susan Richmond, Dante Fratta
Summary: This article presents a method for improving the communication of hydrologic data to the public by connecting data to video representations. The authors collected water-quality and geophysical data using multiple instruments mounted on a canoe and recorded video using GoPro cameras. The data was georeferenced and logged using an Arduino microcontroller. The results show that the low-cost sensors performed well and the data-rich video provided context for the measurements. This method enhances spatial understanding of hydrogeologic systems and facilitates communication and management of sensitive habitats.
Article
Geosciences, Multidisciplinary
Michael Cardiff, Laura Schachter, Jake Krause, Madeline Gotkowitz, Brian Austin
Summary: Increased nitrate concentrations in groundwater and surface waters due to modern agriculture is a widespread and significant environmental issue. However, there is a lack of understanding regarding the specific contributions of individual agricultural fields and practices. In this study, a minimally invasive approach using edge-of-field monitoring and tracer application was developed to calculate annual nitrogen loss to groundwater. Results from a commercial field in Wisconsin showed that nitrogen losses were similar to previous studies, with more than 25% of applied nitrogen leaching to groundwater each year. This method provides a reliable estimation of nitrogen loss when using certain conditions, such as injecting the tracer directly at the water table and analyzing nitrate concentrations in the laboratory.
Article
Environmental Sciences
Lijing Wang, Peter K. Kitanidis, Jef Caers
Summary: Bayesian inversion is commonly used to quantify uncertainty of hydrological variables. This paper proposes a hierarchical Bayesian framework to quantify uncertainty of both global and spatial variables. The authors present a machine learning-based inversion method and a local dimension reduction method to efficiently estimate posterior probabilities and update spatial fields. Using three case studies, they demonstrate the importance of quantifying uncertainty of global variables for predictions and the acceleration effect of the local PCA approach.
WATER RESOURCES RESEARCH
(2022)
Article
Water Resources
Mojtaba Forghani, Yizhou Qian, Jonghyun Lee, Matthew Farthing, Tyler Hesser, Peter K. Kitanidis, Eric F. Darve
Summary: This article presents a reduced-order model (ROM) based approach that utilizes a variational autoencoder (VAE) to compress bathymetry and flow velocity information, allowing for fast solving of bathymetry inverse problems. By constructing ROMs on a nonlinear manifold and employing a Hierarchical Bayesian setting, variational inference and efficient uncertainty quantification can be achieved using a small number of ROM runs.
ADVANCES IN WATER RESOURCES
(2022)
Letter
Geosciences, Multidisciplinary
Carsten Leven, Warren Barrash
Article
Environmental Sciences
Xueyuan Kang, Amalia Kokkinaki, Xiaoqing Shi, Hongkyu Yoon, Jonghyun Lee, Peter K. Kitanidis, Jichun Wu
Summary: This study presents a framework that combines a deep-learning-based inversion method with a process-based upscaled model to estimate source zone architecture (SZA) metrics and mass discharge from sparse data. By improving the estimation method, the upscaled model accurately reproduces the concentrations and uncertainties of multistage effluents, providing valuable input for decision making in remediation applications.
WATER RESOURCES RESEARCH
(2022)
Article
Environmental Sciences
Kan Bun Cheng, Gedeon Dagan, Warren Barrash, Michael Cardiff, Avinoam Rabinovich
Summary: Characterizing aquifer heterogeneity is crucial for accurate flow and transport modeling. This study presents a new approach for statistically analyzing hydraulic properties in continuous pumping tomography tests of phreatic aquifers. The method involves determining equivalent hydraulic conductivity, specific storage, and specific yield at multiple locations and calculating statistical moments assuming random space variables. The results show that the spatial averages of the equivalent properties decrease with distance from the pumping well and stabilize at larger distances, consistent with existing theory.
WATER RESOURCES RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Jeremy R. R. Patterson, Michael Cardiff
Summary: Fractured sedimentary bedrock aquifers are complex flow systems with fast fractures and slow porous media-dominated flow paths. Previous studies have used oscillatory flow testing to characterize single bedrock fractures but relied on an idealized analytical model. This study extends the testing to fractured sedimentary bedrock and suggests that other hydraulic processes are needed to accurately represent pressure propagation.
Article
Environmental Sciences
Simon Meunier, Peter K. Kitanidis, Amaury Cordier, Alan M. MacDonald
Summary: This study develops a numerical model to simulate the abstraction capacities of photovoltaic water pumping systems across Africa using openly available data. The model includes realistic geological constraints on pumping depth and sub-hourly irradiance time series. The simulation results show that for much of Africa, groundwater pumping using photovoltaic energy is limited by aquifer conditions rather than irradiance. These findings can help identify regions with high potential for photovoltaic pumping and guide large-scale investments.
COMMUNICATIONS EARTH & ENVIRONMENT
(2023)